The compound 3-[3-(hexylthio)-1,2,5-thiadiazol-4-yl]-1,2,5,6-tetrahydro-1-methylpyridin e, described in U.S. Pat. No. 5,041,455 ('455), is a compound having muscarinic activity which is indicated for the treatment of Alzheimer's Disease, severe painful conditions and glaucoma. As set forth in the '455 patent, 3-[3-(hexylthio)-1,2,5-thiadiazol-4-yl]-1,2,5,6-tetrahydro-1-methylpyridin e can be prepared in a solid form for oral use, in the form of suppositories for rectal administration, or in the form of sterile injectable solutions for parenteral use. A formulation for a typical tablet is provided; however, the patent does not suggest that it would be possible or desirable to prepare a transdermal 3-[3-(hexylthio)-1,2,5-thiadiazol-4-yl]-1,2,5,6-tetrahydro-1-methylpyridin e patch formulation.
Applicants have discovered that the transdermal 3-[3-(hexylthio)-1,2,5-thiadiazol-4-yl]-1,2,5,6-tetrahydro-1-methylpyridin e patch formulation of this invention provides surprising beneficial effects.
The present invention provides a method for treating Alzheimer's disease with fewer side effects than are typically associated with muscarinic agonists like 3-[3-(hexylthio)-1,2,5-thiadiazol-4-yl]-1,2,5,6-tetrahydro-1-methylpyridin e.
The transdermal formulation of this invention provides consistent dosage of the active ingredient, achieves sustained plasma concentration of the pharmaceutically active agent, and encourages patient compliance.